The National Science Foundation created the LTER program in 1980 to conduct ecological research that could span decades and large geographical areas. The 26 LTER sites encompass the Nations diverse ecosystems—including deserts, lakes, oceans, reefs, prairies, forests, and urban areas.

Articles in the Bioscience issue detail the unique contributions long-term research approaches such as those undertaken at Coweeta bring in an era of unprecedented environmental change while demonstrating how the research is used to inform local- to national-scale decisions about climate change, pollution, fire, land conversion and other pressing challenges.

Established in 1980 as one of the six original LTER sites, the Coweeta LTER Program is a partnership between the University of Georgia and the Coweeta Hydrologic Lab, and one of the oldest continuous environmental studies in North America. Over time the program has evolved from a site-based to a region-based project, moving beyond the Coweeta basin to provide a scientific understanding of the factors behind the land use changes that have taken place in the southern Appalachians over the last 200 years—and to forecast patterns of change in the future.

Coweeta project leader Chelcy Ford and SRS scientist and project leader Jim Vose are co-authors of an article in the special Bioscience issue that reports findings from a study of long-term data from 35 headwater basins in the United States and Canada. The researchers collected data from a total of 10 Forest Service Experimental Forests and Ranges; five of these, including Coweeta, are also LTER sites.

Study sites were headwater basins that have minimal human disturbance since their records began. For Coweeta, researchers took 60 years of climate and streamflow data from a watershed that has not been managed since 1927.

Coweeta was one of 19 sites with long-term (20- to 60-year) records of both streamflow and climate. The data show that the effect of climate change on streamflow is not as clear as expected. Though air temperatures increased significantly at 17 of the 19 sites, including Coweeta, streamflow trends could only by directly related to climate change at the seven sites where ice and snow play a major part in streamflow.

“A key finding of the study is that past and present natural and human disturbances and vegetation succession can mask or even exacerbate the effect of climate change and streamflow,” says Ford. “We’ve also seen this in our studies at Coweeta. The LTER sites offer the capacity to start to understand how human activities interact with climate change to affect future water supplies.”